Adaptive smoothing method, device, terminal and medium for suppressing load inrush current

Abstract

The application discloses a load impact current adaptive smoothing suppression method and device, a terminal and a medium, wherein the load impact current adaptive smoothing suppression method comprises the following steps: collecting current signals at compensation points in real time; judging working conditions based on the current signals at the signal compensation points; if it is determined that the APF / SVG system is in a load sudden working condition, extracting impact current characteristic parameters; constructing an impact current buffer model and a parameter adjustment model based on the impact current characteristic parameters; integrating the impact current buffer model and the parameter adjustment model in a digital control loop of the APF / SVG system, and performing smoothing suppression by adjusting dynamic parameters; through the impact current buffer model and the parameter adjustment model, different impact intensities and rates are dynamically adapted, the impact current peak value and the mutation rate are effectively reduced, the compensation current fluctuation is reduced, and the equipment operation stability and the power grid power quality are significantly improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power equipment control, and particularly relates to a load impact current adaptive smoothing suppression method and device, a terminal and a medium. BACKGROUND

[0002] With the wide application of frequency converters, electric arc furnaces and other nonlinear and impact loads in modern industry, active power compensation devices APF / SVG have become key equipment for ensuring power quality of power grids. However, in actual operation, when a load is suddenly put into or removed, a huge impact current will be generated, and the current has characteristics such as high amplitude, fast change rate, and interwoven harmonic and reactive components. Such impact current will bring severe challenges to the control system of APF / SVG: the impact current generated instantaneously when the load is suddenly added will cause the signal extraction distortion of the harmonic detection module of APF and the reactive detection module of SVG within milliseconds, and then the given compensation current of the device exceeds the rated working range, triggering the overcurrent protection action, and even causing the device shutdown, power grid voltage fluctuation and other chain problems, which seriously threatens the stable operation of the power system.

[0003] The existing APF / SVG control strategy generally adopts a PI control algorithm with fixed parameters, and the proportional coefficient and integral coefficient are preset when the device is shipped, and cannot be dynamically adjusted according to the impact strength of the load. When the load is suddenly added, the PI controller with fixed parameters cannot dynamically adapt to different impact strengths and different impact rates, and lacks adaptive ability. When the impact characteristics change, if the control response is too fast, it is easy to cause current overshoot and aggravate the risk of over-limit; if the control response is too slow, the impact current cannot be suppressed in time, and the extraction distortion problem continues to exist. SUMMARY

[0004] The purpose of the present application is to provide a load impact current adaptive smoothing suppression method to solve the problems of extraction distortion of APF / SVG when the load is suddenly added and control mismatch caused by fixed parameters.

[0005] To solve the above technical problems, the present application provides the following technical solutions, which include: collecting current signals at a compensation point in real time; judging the working condition based on the current signals at the compensation point; if it is determined that the APF / SVG system is in a load sudden working condition, extracting impact current characteristic parameters; constructing an impact current buffer model and a parameter adjustment model based on the impact current characteristic parameters; integrating the impact current buffer model and the parameter adjustment model in the digital control loop of the APF / SVG system, and smoothing suppression by adjusting dynamic parameters.

[0006] As a preferred scheme of the adaptive smoothing suppression method of load impact current, the current signal at the compensation point comprises: filtering the current signal at the compensation point through a third-order Butterworth low-pass filter, and the cutoff frequency is set to 1 kHz to remove the interference of high-frequency noise on signal analysis.

[0007] As a preferred scheme of the adaptive smoothing suppression method of load impact current, the working condition judgment comprises: setting a current change rate threshold a and a current amplitude mutation threshold b, taking the total current in the previous one power frequency period as the basis for the current at the current time t , calculating the moving average value of the total current, and taking the moving average value as the steady-state current reference I steady ; calculating the instantaneous change rate k of the current at the compensation point; calculating the deviation absolute value of the current i pcc (t) at the compensation point at time t from the steady-state current reference I steady ; and determining that the APF / SVG system is in a load impact working condition when k>a and |i pcc (t)-I steady |>b are met.

[0008] As a preferred scheme of the adaptive smoothing suppression method of load impact current, the extraction of the impact current characteristic parameters comprises: analyzing the current signal collected under the load impact working condition, and extracting the impact current peak I peak , the current rise time t r and the impact duration t d respectively. peak : the maximum value of the current after the load is added, used to judge the impact strength and the impact change rate; the current rise time t r : the time for the current to rise from the steady-state value to the impact current peak I peak ; and the impact duration t d : the time for the current to drop from the impact current peak I peak to the rated current range.

[0009] As a preferred scheme of the adaptive smoothing suppression method of load impact current, the impact current buffer model comprises:

[0010] The impact current buffer model is constructed based on the impact strength and the impact rate:

[0011] ;

[0012] In the formula, is a load current buffer coefficient, is a buffer coefficient initial reference value, The peak impact factor of the impact current. This is the peak value of the inrush current. The rated operating current of the APF / SVG system. The impact factor for the rise time is t. r The current rise time As the baseline rise time, This is the influence coefficient of grid voltage fluctuation. This represents the voltage fluctuation value of the power grid when the load suddenly increases. This is the rated voltage of the power grid.

[0013] As a preferred embodiment of the adaptive smoothing suppression method for load inrush current described in this invention, the parameter adjustment model includes:

[0014] The parameter tuning model includes current loop PI parameter tuning and voltage loop PI parameter tuning;

[0015] Current loop PI parameter adjustment includes:

[0016] ;

[0017] ;

[0018] Voltage loop PI parameter adjustment includes:

[0019] ;

[0020] ;

[0021] In the formula, This is the proportionality coefficient of the current loop. This is the reference value for the current loop proportional coefficient. The integral coefficient of the current loop is... This is the reference value for the integral coefficient of the current loop. This is the current loop weighting coefficient. This is the voltage loop proportionality coefficient. This is the reference value for the voltage loop proportional coefficient. This is the voltage loop weighting coefficient. The voltage loop integral coefficient, This is the reference value for the voltage loop integral coefficient.

[0022] As a preferred embodiment of the adaptive smoothing suppression method for load inrush current described in this invention, the smoothing suppression includes:

[0023] The digital control loop of the APF / SVG system comprises a signal acquisition and preprocessing component, a core control and operation component, an execution component and a feedback component; the signal acquisition and preprocessing component is composed of a Hall sensor, a voltage transformer and an ADC module, and is responsible for converting the collected analog signals into digital signals; the core control and operation component is composed of a model operation special-purpose core, a PI controller and a FPGA logic control unit, and is responsible for executing the control algorithm, judging the adaptive smoothing suppression effect and generating a PWM driving instruction; the execution component is composed of an inverter switch tube and a PWM driving circuit, receives the PWM driving instruction output by the FPGA, controls the on-off of the switch tube and outputs a compensation current; and the feedback component is composed of a compensation current feedback sensor and a voltage transformer, collects the power grid voltage fluctuation value and the compensation current output by the execution component in real time, and transmits them back to the core control and operation component to form a closed-loop control.

[0024] The impact current buffer model is integrated into the model operation special-purpose core in the core control and operation component, data collected by the signal acquisition and preprocessing component is called for operation, a load current buffer coefficient a is generated, it is judged whether the slope change rate of the impact current curve is greater than 5, if yes, the a value is transmitted to the PI controller through a preset register mapping address, otherwise, the a value is fine-tuned and transmitted to the PI controller through the preset register mapping address.

[0025] The parameter adjustment model is integrated into the model operation special-purpose core, the current loop PI parameter and the voltage loop PI parameter are generated by operation in combination with the impact current characteristic parameters, it is judged whether the slope change rate of the impact current curve is greater than 5, if yes, the current loop PI parameter and the voltage loop PI parameter are written into the parameter register of the PI controller, otherwise, the current loop PI parameter and the voltage loop PI parameter are fine-tuned and written into the parameter register of the PI controller.

[0026] The PI controller corrects the original given current according to the a value, and obtains a current control target of the PI controller.

[0027] The PWM driving instruction is generated in combination with the current control target and the compensation current according to the current loop PI parameter and the voltage loop PI parameter in the parameter register.

[0028] The execution component receives the generated PWM driving instruction, controls the on-off of the switch tube and outputs the compensation current.

[0029] The feedback component collects the slope change rate of the new impact current curve, judges whether the smoothing suppression effect meets the standard, if yes, the fine-tuning is stopped, otherwise, the slope change rate of the impact current curve, the power grid voltage fluctuation value and the compensation current are transmitted to the core control and operation component for fine-tuning until the smoothing suppression effect meets the standard.

[0030] The application further provides a load impact current adaptive smoothing device for implementing the load impact current adaptive smoothing method according to any one of the above, comprising: a signal acquisition module configured to acquire a current signal at a compensation point in real time; a working condition analysis module configured to judge a working condition based on the current signal at the signal compensation point; a parameter extraction module configured to extract an impact current characteristic parameter if it is determined that the APF / SVG system is in a load sudden change working condition; a model construction module configured to construct an impact current buffer model and a parameter adjustment model based on the impact current characteristic parameter; and a smoothing suppression module configured to integrate the impact current buffer model and the parameter adjustment model into a digital control loop of the APF / SVG system, and perform smoothing suppression by adjusting dynamic parameters.

[0031] The application further provides a terminal device, comprising:

[0032] one or more processors;

[0033] a memory coupled to the processors, for storing one or more programs;

[0034] When the one or more programs are executed by the one or more processors, the one or more processors implement the load impact current adaptive smoothing method according to any one of the above.

[0035] The application further provides a computer readable storage medium having a computer program stored thereon, and the computer program is executed by a processor to implement the load impact current adaptive smoothing method according to any one of the above.

[0036] The application has the following beneficial effects: the impact current buffer model and the parameter adjustment model are used to dynamically adapt to different impact intensities and rates, solve the problems of detection instruction distortion and fixed parameter adjustment inaccuracy, effectively reduce the impact current peak value and mutation rate, reduce the compensation current fluctuation, do not need to add new hardware, adapt to the characteristic differences of APF and SVG, and significantly improve the equipment operation stability and power grid power quality. BRIEF DESCRIPTION OF DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor. Among them:

[0038] Figure 1The flow chart of the load impact current adaptive smoothing suppression method is shown in the first embodiment of the present application. DETAILED DESCRIPTION

[0039] In order to make the above objectives, features and advantages of the present application more apparent, the specific embodiments of the present application will be described in detail below with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative work should fall within the protection scope of the present application.

[0040] In the following description, a large number of specific details are set forth in order to facilitate a thorough understanding of the present application. However, the present application can be implemented in other different manners than those described herein, and those skilled in the art can make similar generalizations without departing from the spirit and scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0041] Secondly, the term "one embodiment" or "an embodiment" as used herein means that a specific feature, structure or characteristic described in the embodiment can be included in at least one implementation of the present application. The term "in one embodiment" appearing in different places in the specification does not mean the same embodiment, nor does it mean that the embodiment is separate or alternative to other embodiments.

[0042] The present application is described in detail in conjunction with the schematic drawings. In the detailed description of the embodiments of the present application, the sectional view of the device structure is locally enlarged without the general proportion for the convenience of description, and the schematic drawings are only examples, which should not limit the protection scope of the present application herein. In addition, the three-dimensional spatial dimensions of length, width and depth should be included in the actual manufacture.

[0043] Meanwhile, in the description of the present application, it should be noted that the terms "upper, lower, inner and outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first, second or third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0044] In the present application, unless otherwise explicitly specified and limited, the terms "mounting, connection, connection" should be understood in a broad sense, for example: it can be fixed connection, detachable connection or integral connection; it can also be mechanical connection, electrical connection or direct connection, it can also be indirectly connected through an intermediate medium, or it can be the communication between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0045] Example 1

[0046] Reference Figure 1 This is the first embodiment of the present invention, which provides an adaptive smoothing suppression method for load inrush current, comprising:

[0047] S1: Real-time acquisition of current signals at compensation points.

[0048] The compensation point, also known as the PCC point or point of common coupling, is the vector sum of the system load current and the APF / SVG compensation current. However, at the initial moment of a load surge, its changing characteristics are mainly determined by the load surge. Preferably, this invention does not require the installation of additional detection devices in the load branch. By simply collecting the inherent total current signal at the APF / SVG device grid connection point (PCC point), the impact event can be quickly determined at the initial stage of a load surge by monitoring the rate of change and amplitude deviation of this signal. This greatly simplifies the system structure, reduces costs, and improves reliability.

[0049] Furthermore, the current signal at the compensation point is filtered using a third-order Butterworth low-pass filter with a cutoff frequency of 1kHz to remove high-frequency noise interference with signal analysis.

[0050] S2: Determine the operating condition based on the current signal at the compensation point.

[0051] Set a current change rate threshold 'a' and a current amplitude abrupt change threshold 'b' (to confirm the significance of current changes, with values ​​ranging from 20% to 30% of the equipment's rated current). The current change rate threshold 'a' is used to sense the rate of abrupt changes in current, with a value ranging from 50 A / ms to 100 A / ms, which can be adjusted according to the equipment's rated current. The current amplitude abrupt change threshold 'b' is used to confirm the significance of current changes, with a value ranging from 20% to 30% of the equipment's rated current.

[0052] Based on the current time t, take the previous power frequency cycle. Calculate the moving average of the total current within the range. This is used as the steady-state current reference I. steady To enhance anti-interference capabilities;

[0053] Calculate the instantaneous rate of change of current at the compensation point, k = di pcc (t) / dt;

[0054] Calculate the current i at the compensation point at time t. pcc (t) and steady-state current reference I steady The absolute value of the deviation: |i pcc (t)-I steady |;

[0055] When the rate of change k > a and the magnitude of change |i pcc (t)-I steady When |>b, it is determined that the APF / SVG system is under a sudden load condition.

[0056] S3: If the APF / SVG system is determined to be under sudden load conditions, extract the inrush current characteristic parameters.

[0057] The current signals collected under sudden load conditions were analyzed, and the peak impact current I was extracted. peak Current rise time t r and impact duration t d :

[0058] Peak inrush current I peak The maximum current reached after a sudden load application is used to determine the impact intensity and the rate of impact change; I peak The larger the value, the more severe the impact, and the greater the subsequent buffering required, i.e., reducing the load current buffering coefficient α.

[0059] Current rise time t r The current rises from its steady-state value to the peak impulse current I. peak Time; t r The shorter the time, the faster the current change, and the stronger the buffer response needs to be. The load current buffer coefficient α is adjusted by the impact rise time influence coefficient k2.

[0060] Impact duration t d Current from the peak value of the inrush current I peak Time to drop to within the rated current range; impact duration t d Used to determine the duration of impact effects, t d The longer the duration, the longer the execution cycle of adaptive smoothing suppression needs to be to avoid premature exit leading to secondary impacts.

[0061] S4: Construct an impulse current buffer model and a parameter adjustment model based on the impulse current characteristic parameters.

[0062] An impact current buffering model is constructed based on impact intensity and impact velocity:

[0063] ;

[0064] In the formula, This is the load current buffer coefficient, used to dynamically attenuate the given current of APF / SVG. The smaller the value, the stronger the buffering effect; the larger the value, the weaker the buffering effect. This is the initial baseline value for the buffer coefficient, which is adjusted according to the equipment's shock resistance (e.g., 0.85 for equipment with strong shock resistance and 0.75 for equipment with weak shock resistance). This is the peak impact coefficient of the inrush current, used to enhance the peak suppression effect; This is the peak value of the inrush current. The rated operating current of the APF / SVG system. The impact rise time influence coefficient is used to enhance rapid impact suppression; t r The current rise time As the baseline rise time, This is the influence coefficient of grid voltage fluctuations, to avoid current exacerbating voltage instability; This refers to the voltage fluctuation value of the power grid when the load suddenly increases, i.e., the deviation between the actual voltage value and the rated value; This is the rated voltage of the power grid.

[0065] The load current buffering coefficient α is linked in real time with the impact characteristics and the power grid status to achieve on-demand buffering. The specific principle is as follows:

[0066] Impact strength adaptation: Passing an impact current exceeding the rated ratio and peak impact coefficient of impact current The stronger the impact, the smaller the α value, and the greater the buffering effect.

[0067] Impact rate adaptation: by the ratio of actual rise time to reference time. Impact coefficient of shock rise time The slower the impact, the larger α is, and the smaller the buffering effect;

[0068] Voltage state adaptation: via voltage fluctuation ratio And the influence coefficient of grid voltage fluctuation The greater the voltage fluctuation, the smaller α, and the greater the buffering effect.

[0069] A parameter adjustment model is constructed based on PI parameters, buffer coefficients, and inter-loop weights. The parameter adjustment model includes a current loop PI parameter adjustment model and a voltage loop PI parameter adjustment model.

[0070] The current loop PI parameter adjustment model (controlling inrush current) includes:

[0071] ;

[0072] ;

[0073] The voltage loop PI parameter regulation model (for stabilizing grid voltage) includes:

[0074] ;

[0075] ;

[0076] In the formula, This is the proportional coefficient of the current loop, used to control the speed of current response; the larger the value, the faster the response. This is the reference value for the current loop proportional coefficient. This is the integral coefficient of the current loop, used to control the ability to eliminate steady-state current errors; the larger the value, the faster the error is eliminated. This is the reference value for the integral coefficient of the current loop. This is the current loop weighting coefficient, used to control the proportion of the influence of the current loop parameters in the dual closed loop; This is the voltage loop proportional coefficient, used to control the speed of voltage response; the larger the value, the faster the voltage adjustment. This is the reference value for the voltage loop proportional coefficient. This is the voltage loop weighting coefficient, used to control the proportion of the influence of voltage loop parameters in the dual closed loop; This is the voltage loop integral coefficient, used to control the ability to eliminate steady-state voltage errors. The larger the value, the faster the voltage error is eliminated. This is the reference value for the voltage loop integral coefficient.

[0077] S5: The inrush current buffer model and parameter adjustment model are integrated into the digital control loop of the APF / SVG system to achieve smooth suppression by adjusting dynamic parameters.

[0078] The digital control loop of an APF / SVG system includes signal acquisition and preprocessing components, core control and computation components, execution components, and feedback components.

[0079] The signal acquisition and preprocessing component consists of a Hall sensor, a voltage transformer, and an ADC module, which is responsible for converting the acquired analog signals into digital signals and transmitting them to the core control and computing components.

[0080] The core control and computation component is responsible for executing control algorithms, judging the adaptive smoothing suppression effect, and generating PWM drive commands. It consists of a dedicated model computation core, a PI controller, and an FPGA logic control unit. The dedicated model computation core performs calculations on the inrush current buffer model and parameter adjustment model, generating the load current buffer coefficient α and PI parameters. When the adaptive smoothing suppression effect is insufficient, it fine-tunes the load current buffer coefficient α and PI parameters. The PI controller is used to generate the basic duty cycle for the PWM drive command. The FPGA logic control unit is used to perform logic optimization on the basic duty cycle output by the PI controller to generate the final PWM drive command, avoiding damage to the switching transistor.

[0081] The execution component consists of inverter switching transistors and PWM drive circuits. It receives PWM drive commands from the FPGA, controls the switching transistors to turn on and off, and outputs compensation current.

[0082] The feedback component consists of a compensation current feedback sensor and a voltage transformer. It collects the grid voltage fluctuation value and the compensation current output by the execution component in real time, and transmits them back to the core control and computing component to form a closed-loop control.

[0083] The inrush current buffer model is integrated into the dedicated model calculation core in the core control and computing components. It calls the data collected by the signal acquisition and preprocessing components to perform calculations and generate the load current buffer coefficient α. It then checks whether the slope change rate of the inrush current curve is greater than 5. If it is, it indicates that the adaptive smoothing suppression effect is not up to standard. In this case, the α value needs to be transmitted to the PI controller through the preset register mapping address. Otherwise, the α value is fine-tuned and transmitted to the PI controller through the preset register mapping address.

[0084] The parameter adjustment model is integrated into the dedicated model calculation core. Combined with the impact current characteristic parameters, the current loop PI parameters and voltage loop PI parameters are calculated and generated. It is determined whether the slope change rate of the impact current curve is greater than 5. If it is, it is written to the PI controller parameter register. Otherwise, the current loop PI parameters and voltage loop PI parameters are fine-tuned and written to the PI controller parameter register.

[0085] The PI controller corrects the original given current based on the α value to obtain the current control target of the PI controller;

[0086] Based on the current loop PI parameters and voltage loop PI parameters in the parameter register, and combined with the current control target and compensation current, a PWM drive instruction is generated.

[0087] The execution component receives and generates PWM drive instructions, and outputs compensation current by controlling the switching transistor to turn on and off;

[0088] The feedback component collects the slope change rate of the new inrush current curve to determine whether the smoothing and suppression effect meets the standard. If it is greater than 5, the fine-tuning stops. Otherwise, the slope change rate of the inrush current curve, the grid voltage fluctuation value, and the compensation current are transmitted to the core control and calculation component for fine-tuning until the smoothing and suppression effect meets the standard.

[0089] Example 2

[0090] This invention provides an adaptive smoothing and suppression device for load inrush current, used to implement the steps of the adaptive smoothing and suppression method for load inrush current as described in any of the above embodiments. The adaptive smoothing and suppression device for load inrush current includes:

[0091] The signal acquisition module is configured to perform real-time acquisition of the current signal at the compensation point;

[0092] The operating condition analysis module is configured to perform operating condition judgment based on the current signal at the signal compensation point;

[0093] The parameter extraction module is configured to extract the impact current characteristic parameters if the APF / SVG system is determined to be under a sudden load condition.

[0094] The model building module is configured to perform the construction of an impact current buffer model and a parameter adjustment model based on the impact current characteristic parameters.

[0095] The smoothing and suppression module is configured to execute a digital control loop that integrates the inrush current buffer model and the parameter adjustment model into the APF / SVG system, and to perform smoothing and suppression by adjusting dynamic parameters.

[0096] Example 3

[0097] This embodiment provides a terminal device, including:

[0098] One or more processors;

[0099] A memory, coupled to the processor, for storing one or more programs;

[0100] When the one or more programs are executed by the one or more processors, the one or more processors implement the adaptive smoothing suppression method for load surge current as described above.

[0101] The processor controls the overall operation of the terminal device to complete all or part of the steps of the adaptive smoothing suppression method for load inrush current described above. The memory stores various types of data to support the operation of the terminal device. This data may include, for example, instructions for any application or method operating on the terminal device, as well as application-related data. The memory can be implemented using any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read-Only Memory (EPROM), Programmable Read-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk.

[0102] The terminal device can be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components to perform the adaptive smoothing suppression method for load inrush current as described in any of the above embodiments, and achieve the same technical effect as the above method.

[0103] Example 4

[0104] This embodiment provides a computer-readable storage medium whose program instructions, when executed by a processor, implement the steps of the adaptive smoothing suppression method for load inrush current as described in any of the above embodiments. For example, the computer-readable storage medium can be the memory including the program instructions, which can be executed by a processor of a terminal device to complete the adaptive smoothing suppression method for load inrush current as described in any of the above embodiments, and achieve the same technical effect as the above method.

[0105] It should be recognized that embodiments of the present invention can be implemented or carried out by computer hardware, a combination of hardware and software, or by computer instructions stored in a non-transitory computer-readable storage medium. The method can be implemented using standard programming techniques—including a non-transitory computer-readable storage medium configured with a computer program, wherein such a storage medium causes the computer to operate in a specific and predefined manner—according to the methods and drawings described in the specific embodiments. Each program can be implemented in a high-level procedural or object-oriented programming language to communicate with the computer system. However, if desired, the program can be implemented in assembly or machine language. In any case, the language can be a compiled or interpreted language. Furthermore, for this purpose, the program can run on a programmed application-specific integrated circuit (ASIC).

[0106] Furthermore, the procedures described herein may be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by the context. The procedures described herein (or variations and / or combinations thereof) may be executed under the control of one or more computer systems configured with executable instructions, and may be implemented by hardware or a combination thereof as code (e.g., executable instructions, one or more computer programs, or one or more applications) that commonly executes on one or more processors. The computer program comprises a plurality of instructions executable by one or more processors.

[0107] Furthermore, the method can be implemented in any suitable type of computing platform, including but not limited to personal computers, minicomputers, mainframes, workstations, networked or distributed computing environments, standalone or integrated computer platforms, or in communication with charged particle tools or other imaging devices, etc. Aspects of the invention can be implemented as machine-readable code stored on a non-transitory storage medium or device, whether removable or integrated into a computing platform, such as a hard disk, optical read and / or write storage medium, RAM, ROM, etc., such that it is readable by a programmable computer, and when the storage medium or device is read by the computer, it can be used to configure and operate the computer to perform the processes described herein. Furthermore, the machine-readable code, or portions thereof, can be transmitted via wired or wireless networks. The invention described herein includes these and other different types of non-transitory computer-readable storage media when such media comprises instructions or programs that implement the steps described above in conjunction with a microprocessor or other data processor. When programmed according to the methods and techniques described herein, the invention also includes the computer itself. A computer program can be applied to input data to perform the functions described herein, thereby transforming the input data to generate output data stored in non-volatile memory. The output information can also be applied to one or more output devices such as a display. In a preferred embodiment of the invention, the converted data represents physical and tangible objects, including specific visual depictions of physical and tangible objects generated on a display.

[0108] As used herein, the terms “component,” “module,” “system,” etc., are intended to refer to a computer-related entity, which may be hardware, firmware, a combination of hardware and software, software, or running software. For example, a component may be, but is not limited to, a process running on a processor, a processor, an object, an executable file, a running thread, a program, and / or a computer. As an example, an application running on a computing device and the computing device itself can both be components. One or more components may reside in a running process and / or thread, and components may be located in a single computer and / or distributed among two or more computers. Furthermore, these components are capable of execution from various computer-readable media having various data structures thereon. These components may communicate locally and / or remotely via signals, such as those containing one or more data packets (e.g., data from a component that interacts with a local system, another component in a distributed system, and / or signals that interact with other systems via a network such as the Internet).

[0109] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. An adaptive smoothing and suppression method for load inrush current, characterized in that, include: Real-time acquisition of current signals at compensation points; The operating condition is determined based on the current signal at the compensation point. If the APF / SVG system is determined to be under sudden load conditions, then the inrush current characteristic parameters are extracted; An impulse current buffer model and a parameter adjustment model are constructed based on the impulse current characteristic parameters. The inrush current buffer model and parameter adjustment model are integrated into the digital control loop of the APF / SVG system, and smooth suppression is achieved by adjusting dynamic parameters. The inrush current buffer model includes: An impact current buffering model is constructed based on impact intensity and impact velocity: In the formula, This is the load current buffer coefficient. This is the initial baseline value for the buffer coefficient. This is the peak impact coefficient of the impact current. This is the peak value of the inrush current. The rated operating current of the APF / SVG system. The impact factor for the rise time is t. r The current rise time As the baseline rise time, The voltage fluctuation impact coefficient of the power grid. This represents the voltage fluctuation value of the power grid when the load suddenly increases. This is the rated voltage of the power grid; The parameter adjustment model includes: The parameter adjustment models include the current loop PI parameter adjustment model and the voltage loop PI parameter adjustment model; The current loop PI parameter adjustment model includes: The voltage loop PI parameter adjustment model includes: In the formula, This is the proportionality coefficient of the current loop. This is the reference value for the current loop proportional coefficient. The integral coefficient of the current loop is... This is the reference value for the integral coefficient of the current loop. This is the current loop weighting coefficient. This is the voltage loop proportionality coefficient. This is the reference value for the voltage loop proportional coefficient. This is the voltage loop weighting coefficient. The voltage loop integral coefficient, This is the reference value for the voltage loop integral coefficient; The smoothing suppression includes: The digital control loop of the APF / SVG system includes a signal acquisition and preprocessing component, a core control and computation component, an execution component, and a feedback component. The signal acquisition and preprocessing component, consisting of Hall effect sensors, voltage transformers, and an ADC module, is responsible for converting acquired analog signals into digital signals. The core control and computation component, composed of a dedicated model computation core, a PI controller, and an FPGA logic control unit, is responsible for executing control algorithms, judging the adaptive smoothing and suppression effect, and generating PWM drive commands. The execution component, consisting of inverter switching transistors and a PWM drive circuit, receives PWM drive commands from the FPGA, controls the switching transistors' on / off states, and outputs compensation current. The feedback component, consisting of a compensation current feedback sensor and a voltage transformer, collects real-time grid voltage fluctuations and the compensation current output by the execution component, and transmits this data back to the core control and computation component, forming a closed-loop control. The impulse current buffer model is integrated into the dedicated model calculation core in the core control and calculation component. The data collected by the signal acquisition and preprocessing component is called to perform calculations to generate the load current buffer coefficient α. It is determined whether the slope change rate of the impulse current curve is greater than 5. If it is greater, the α value is transmitted to the PI controller through the preset register mapping address. Otherwise, the α value is fine-tuned and transmitted to the PI controller through the preset register mapping address. The parameter adjustment model is integrated into the dedicated core for model calculation. Combined with the impact current characteristic parameters, the current loop PI parameters and voltage loop PI parameters are calculated and generated. It is determined whether the slope change rate of the impact current curve is greater than 5. If it is, it is written into the parameter register of the PI controller. Otherwise, the current loop PI parameters and voltage loop PI parameters are fine-tuned and written into the parameter register of the PI controller. The PI controller corrects the original given current based on the α value to obtain the current control target of the PI controller; Based on the current loop PI parameters and voltage loop PI parameters in the parameter register, and combined with the current control target and compensation current, a PWM drive instruction is generated. The execution component receives and generates PWM drive instructions, and outputs compensation current by controlling the switching transistor to turn on and off; The feedback component collects the slope change rate of the new inrush current curve to determine whether the smoothing and suppression effect meets the standard. If it is greater than 5, the fine-tuning stops. Otherwise, the slope change rate of the inrush current curve, the grid voltage fluctuation value, and the compensation current are transmitted to the core control and calculation component for fine-tuning until the smoothing and suppression effect meets the standard.

2. The adaptive smoothing and suppression method for load inrush current as described in claim 1, characterized in that, The current signal at the compensation point includes: The current signal at the compensation point is filtered using a third-order Butterworth low-pass filter with a cutoff frequency of 1kHz to remove high-frequency noise interference with signal analysis.

3. The adaptive smoothing and suppression method for load inrush current as described in claim 2, characterized in that, The operating condition judgment includes: Set a threshold for the rate of change of current, 'a', and a threshold for the sudden change in current amplitude, 'b'. Using the current time 't' as a reference, take the total current within the previous power frequency cycle 'τ' and calculate its moving average. This is used as the steady-state current reference I. steady ; Calculate the instantaneous rate of change k of the current at the compensation point; Calculate the current i at the compensation point at time t. pcc (t) and steady-state current reference I steady The absolute value of the deviation; When k>a and |i pcc (t)-I steady When |>b, it is determined that the APF / SVG system is under a sudden load condition.

4. The adaptive smoothing and suppression method for load inrush current as described in claim 3, characterized in that, The extracted impulse current characteristic parameters include: The current signals collected under sudden load conditions were analyzed, and the peak impact current I was extracted. peak Current rise time t r and impact duration t d : Peak inrush current I peak The maximum current reached after a sudden load application is used to determine the impact intensity and the rate of impact change. Current rise time t r The current rises from its steady-state value to the peak impulse current I. peak Time; Impact duration t d Current from the peak value of the inrush current I peak The time it takes for the current to drop back to within the rated current range.

5. An adaptive smoothing and suppression device for load inrush current, used to implement the adaptive smoothing and suppression method for load inrush current as described in any one of claims 1 to 4, characterized in that, The adaptive smoothing and suppression device for the load inrush current includes: The signal acquisition module is configured to perform real-time acquisition of the current signal at the compensation point; The operating condition analysis module is configured to perform operating condition judgment based on the current signal at the compensation point; The parameter extraction module is configured to extract the impact current characteristic parameters if the APF / SVG system is determined to be under a sudden load condition. The model building module is configured to perform the construction of an impact current buffer model and a parameter adjustment model based on the impact current characteristic parameters. The smoothing and suppression module is configured to execute a digital control loop that integrates the inrush current buffer model and the parameter adjustment model into the APF / SVG system, and to perform smoothing and suppression by adjusting dynamic parameters.

6. A terminal device, characterized in that, include: One or more processors; A memory, coupled to the processor, for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the adaptive smoothing suppression method for load surge current as described in any one of claims 1 to 4.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, The computer program is executed by a processor to implement the adaptive smoothing suppression method for load inrush current as described in any one of claims 1 to 4.

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